The Bioanalytical Core will serve all projects in this Program. It will consist of an Analytical component (directed by Dr. Blair-Center for Cancer Pharmacology, University of Pennsylvania), and a Synthetic component (directed by Dr. Harvey-The Ben May Institute, University of Chicago). The major roles of the Analytical component are: 1) to assess the purity of PAHmetabolites used by all Project Investigators (Projects 1-3), and this is pertinent to the use of anti- and syn-diol epoxides which hydrolyze to tetraols; 2) to quantitate PAH-metabolites formed in cell culture experiments, once structural validation of the analyte has been achieved; 3) to quantitate concentrations of PAH-o-quinones used in cell culture experiments, once structural validation of the analyte has been achieved; 4) to quantitate covalent modifications to DNA by PAH-metabolites and reactive oxygen species in Project 1 once methods development and validation has been achieved in Project 2; and 5) with support from the Administrative Core A to act as a liaison between the NCI Chemical Carcinogen Reference Standard Repository and Project Investigators to maintain stocks of individual PAH-metabolites and PAH-synthons. The analytical component will be reliant on a PAH-Database and a Program Database maintained in the Administrative Core-A these will monitor stocks of PAH-metabolites and perform statistical analysis of PAH-DNA adducts. The Analytical component of Core B contains a triple-quadruple mass spectrometer and an ion-trap mass spectrometer. The Synthetic component of Core B will develop efficient synthetic strategies to: 1) the major stable benzo[a]pyrene diol-epoxide (BPDE) adducts [(+) and (-)-anti-BPDE-N6-dAdo (trans-isomers); (+) and (-)-anti-BPDE-N6 dAdo (cis-isomers), (+) and (-) anti-BPDE-N2-dGuo (trans-isomers) (+)-and (-)-anti-BPDE-N2-dGuo (cisisomers)], major radical-cation BP depurination adducts [N7- and C8-guanine and N7-adenine adducts of BP], and the stable and depurinating adducts of BP-2 7,8-dione [N -dGuo, N6-dAdo, N7-guanine and N7-adenine]. These reference standards will be used in Projects 1 and 2 to identify unknowns; and 2) to develop synthetic strategies to the stable and depurinating adducts of BA-3,4- dione [N2-dGuo, N6-dAdo, N7-guanine and N7-adenine] and the stable and depurinating adducts of DMBA-3,4-dione [N2-dGuo, N6-dAdo, N7-guanine and N7- adenine] for their detection in cell culture paradigms in collaboration with Project 1. Via Core A, we will inform the Repository of the availability of novel PAH-DNA adducts for distribution to the PAH-research community. This will establish a symbiotic relationship between Core B and the Repository. Thus, Core B is a vital component to the success of all Projects of the PPG and may impact PAH-DNA adduct research in general.